100 QUESTIONS IN CARDIOLOGY

27 What are the contraindications to thrombolytic

therapy for acute myocardial infarction? Is

diabetic retinopathy a contraindication?

Kenneth W Mahaffey

Haemorrhagic complications (particularly intracranial) are the

most important risks associated with thrombolysis. The 1996

ACC/AHA guidelines for the management of acute myocardial

infarction list four absolute contraindications to thrombolytic

therapy:

• Previous haemorrhagic stroke or other stroke within one year


• Known intracranial neoplasm


• Active internal bleeding (excluding menses)


• Suspected aortic dissection.

In cases where the nature of the stroke (haemorrhagic or

otherwise) is unknown, then the risk of notadministering a

thrombolytic agent should be considered. The majority of strokes

are occlusive in origin, and thus lack of certain knowledge should

probably not represent a contraindication to thrombolysis in those

patients (such as those with extensive territories of myocardial

infarction who present early) who have most to gain.

In addition, there are relative contraindications for which the

potential risks need to be assessed against the anticipated benefits:

• Uncontrolled hypertension or history of chronic severe hyper-

tension

• Known bleeding diathesis or anticoagulant therapy with INR

2–3

• Trauma or internal bleeding (within 2–4 weeks), major surgery

(<3 weeks), prolonged CPR (>10 minutes), non-compressible

vascular puncture, active peptic ulcer

• Pregnancy


• For streptokinase/anistreplase – prior exposure (with 5 days to

2 years) or prior allergic reaction.

Ocular haemorrhage after thrombolysis has been reported, and

diabetic retinopathy was once considered a relative contra-

indication to thrombolytic therapy in AHA/ACC guidelines.